I updated my solution containing multiple silverlight navigation style projects and notice that while the utility properly updates the references in my projects, it fails to update the namespace references in the xaml files. Maybe because you didn't think to test with silverlight navigation apps which derive from Page instead of UserControl - the XAML looks like:
<navigation:Page x:Class="MolallaFM.Views.ONTs"
xmlns:ig="clr-namespace:Infragistics.Controls.Grids;assembly=InfragisticsSL4.Controls.Grids.XamGrid.v11.1"
xmlns:igm="clr-namespace:Infragistics.Controls.Menus;assembly=InfragisticsSL4.Controls.Menus.XamMenu.v11.1"
I basically have to open each XAML file and change the v11.1 to v11.2 which isn't a big deal, but I'm pretty sure the VU is suppose to do that also no???
Sorry to hear about your issue with the utility. Would you be able to send us a simple project that uses this navigation:page? The utility should search all .xaml files an look for our references. I'll have DS open an case with you to get the project, or some more details.
Just add a project of type "Silverlight Navigation Application" to any project shoudl be enough to duplicate the problem. I believe that "Silverlight Business Application" would also work. If you can't duplicate that, drop me an e-mail and I will send you my XAML.